As a graduate student Dr. Carol Greider was studying molecular biology at the University of California Santa Barbara in the laboratory of Dr. Elizabeth Blackburn, who had discovered telomeres just a few years earlier.
Greider was investigating the fact that while every time a cell divides it gets shorter, but telomeres–those end caps protecting the strands of DNA, don’t shorten. Knowing there must be something happening to the telomeres to keep their length at equilibrium, they started searching for evidence of an enzyme that can accomplish this task using the model organism Tetrahymena thermophila.
On Christmas Day, 1984, Greider found the first biochemical evidence that telomeres could be lengthened by an enzyme initially called telomere terminal transferase, now shortened to telomerase. Six months of follow up research led to the conclusion that this enzyme keeps telomeres from wearing down and leaving DNA strands open and vulnerable.
After two more years of research, Greider finished up her doctorate and moved to the Cold Spring Harbor Laboratory as an independent research fellow, continuing her investigations on telomerase. During her time at this lab she was able to clone telomerase and study its function and role in cells. Some of her findings include that unlike most cells in the adult human body, cancer cells contain active forms of telomerase that enable cells to keep dividing by maintaining the length of their chromosome ends allowing these cells to continue growing as immortalized cells. Subsequent work confirmed that inhibition of telomerase can limit cancer cell division and tumor production on cultured human cells and could trigger death in cancer cells but not normal cells.
Work with colleagues at the lab also provided early evidence that telomere length is related to cellular aging and has opening up research in anti-aging efforts.
Offered a research position at Johns Hopkins University in the Department of Molecular Biology, she joined the school’s faculty in 1997 and was promoted to director of the department five years later. After years of researching telomeres and telomerase Drs. Greider, Blackburn, and Jack Szostak shared the Nobel Prize in Medicine awarded in 2009.
Written by Angela Goad